This invention relates to nitrates.
Calcium and magnesium nitrates are used extensively in industry and agriculture. The commercially available products both contain water of crystallization. Calcium nitrate contains about 30 percent water of crystallization and magnesium nitrate about 39 percent water of crystallization The presence of this water leads to problems in storage of the product and causes problems when used in blends with each other and with other materials.
At present calcium nitrate crystals are made commercially with the addition of about 6 percent ammonium nitrate to form a double salt which contains 15 percent water of crystallization. The double salt crystals are formed on a cooling belt and crushed or formed into a prill in a prilling tower.
The formation of magnesium nitrate heptahydrate crystals or prills is a lesser problem because of the higher melting point of magnesium nitrate.
A blend of calcium and magnesium nitrates is a useful product in agriculture, but is difficult to manufacture because of the difficulty in crystallizing the mixture. To date there is no known commercial method of making such a blend or mixture.